The invention relates to a package box formed of a plastic material for flat objects having relatively small dimensions and including a box main part having a shape of a rectangular parallelepiped formed of a bottom, two longitudinally extending side walls and two transversely extending end walls projecting upward from the bottom and defining an upper box opening. The main part has a longitudinally extending separation wall projecting upward from the bottom and located in a longitudinal middle plane of the box along an entire length of the box, and a plurality of transverse separation walls. The height of the transverse separation walls and the end walls is smaller than the height of the side walls. The box further includes a cover for closing the box opening displaceable in a longitudinal direction of the box and having an inner surface lying, in a closed condition of the box, on upper edges of the separation and end walls and on guide beads provided on the longitudinally extending side walls, and an outer surface located beneath a plane defined by the upper edges of the longitudinally extending side walls.
Such boxes can have different dimensions and include means for preventing the cover from unintended displacement in the closed position of the package box.
In some of the boxes, one of the end walls has the same height as the side walls while the other of the end walls has a smaller height equal to the height of the separation walls, so that the cover can be displaced only in one direction. In other boxes, both end walls have a height equal to that of the separation walls, so that the cover can be displaced in both directions.
The above-described box should generally be so formed that the objects to be stored, e.g., cutting inserts, can be placed in cells formed by the separation walls by an automatized process, with the box being closed likewise by an automatized process in which advantageously the cover is placed conveniently from above. Such placement of the cover becomes complicated when not only the side walls of the box but also one of the end walls of the box has a height exceeding that of the separation walls, because the placement would then require another reference point in addition to those associated with the side walls. Further, the automatized placement of the cover requires that the upper edge region of the side walls be somewhat yieldable so that the cover is able to slide along the side steps which hold it at a proper level. However, the one end wall stiffens the side walls in the upper end region, so that in the vicinity of this end wall, the placement of the cover from above cannot be always effected perfectly and, therefore, complete closing of the box cannot be insured.
Another drawback of an end wall having the height equal to that of the side walls consists in that for removal from the box objects, which are located further away from this end wall, the cover should necessarily be moved in the opening direction a longer distance so that the cover forms a longer lever that, under operational conditions at which, e.g., the cutting inserts are handled, can lead to overturning of the box and, thus, to the loss or the damage of the objects.
The above-described boxes have to meet another requirement, namely, to insure that no unintended displacement of the cover in a longitudinal direction takes place. This can be insured by providing, on an inner surface of the cover, a hump which would abut the inner surface of the end wall and which could, possibly, define the closing direction, or by providing for sidewise pressure on the basis of the selected material of the box, e.g., polystyrol, so that a hump or the like would not be needed. However, these methods of retaining the cover are not reliable and can result in an unintended displacement of the cover and a partial opening of the boxes during transportation, or in such behavior of the boxes by themselves, with a possibility of the objects falling out from cells located adjacent to the end wall.
Accordingly, the object of the invention is a package box of the above-described type, in which the cover can be reliably brought in the closing position of the box by an automatized process and reliably retained in the closing position.
Another object of the invention is a package box in which the cover can be displaced in both opposite longitudinal directions above the end walls slightly more than a half of its overall length, so that the cover would cover cells still containing the objects.